1. Field of the Invention
The present invention relates to a paving materials loading apparatus for loading paving materials such as asphalt mixture or the like into a hopper, and to a paving machine such as an asphalt finisher or the like, mounting the screed.
This application is based on patent application No. Hei 10-48208, Hei 10-48209, Hei 10-48211, Hei 10-48212, Hei 10-51128, Hei 10-58684, Hei 10-214610, and Hei 10-372183 filed in Japan, the content of which is incorporated herein by reference.
2. Description of the Related Art
A paving machine as shown in FIG. 38 has been proposed (Published Japanese Translation No. Hei 9-505370 of PCT International Application). This paving machine comprises, mounted on a self-propelled vehicle 81, a front hopper 82, a rear hopper 83, a front spreading screw 85 for spreading paving materials Ha such as asphalt mixture or the like fed from the front hopper 82 via a feeder (not shown), a rear spreading screw 87 for spreading sideways paving materials Hb fed from the rear hopper 83 via a feeder 86, a front screed 88 for laying and paving the paving materials Ha spread by the front spreading screw 85, and a rear screed 89 for laying and paving the paving materials Hb spread by the rear spreading screw 87 onto the road surface. The front screed 88 is supported by an arm 90 extending rearward under the feeder 86, and the rear screed 89 is suspended by a pair of left and right leveling arms 92 which are supported by a pivot shaft 91 on the self-propelled vehicle 81 so as to be pivotal up and down.
The feeder 86 is provided with a conveyor which is formed by an endless belt passing around two rotation shafts, and a screw connected to the rotation shafts on the input side of the conveyor, which feeds the paving materials in the hopper to the conveyor side.
With this paving machine, two kinds of paving materials Ha and Hb can be laid and paved one on top of the other on the road surface at the same time with one paving operation.
However in the case of this paving machine, in order to supply the paving materials Hb to the rear hopper 83 this must be loaded into the rear hopper 83 over the front hopper 82. Accordingly, there is the problem that a dump truck or the like with a dedicated loading apparatus must be used.
Furthermore, since the paving machine is provided with hoppers 82, 83 and the screeds 88, 89 respectively positioned in pairs at the front and rear, the machine itself becomes large, interrupting the front view of an operator who sits on a driving seat at the rear of the vehicle. Therefore, the driving seat is provided at a high position to widen the front view of the operator. A high driving seat however causes problems such as when the paving machine is loaded on a trailer and deadheaded, the trailer cannot pass through a tunnel having a low ceiling, or that it is not convenient for the operator to get on and off.
Moreover, since the front screed 88 is independently supported by the arm 90 of the rear screed 89 which is suspended from the leveling arms 92, then when the paving materials Hb are laid and paved by the rear screed 89 on top of the paving materials Ha paved by the front screed 88, there is the problem that the paving thickness of the upper paving materials Hb cannot be accurately controlled.
Furthermore, since two hoppers, namely the front hopper 82 and the rear hopper 83, are mounted, then as a result of holding a space to arrange both the hoppers 82 and 83 there is the problem that the whole paving machine becomes large. To reduce the size of the paving machine it has been considered to narrow the space for locating the hoppers. In this case however, the volume of the hoppers 82, 83 is reduced and hence the operation of loading the paving materials into the hoppers 82, 83 must be performed frequently. Therefore, there is the problem for dropping the operating efficiency.